Contents Aqueous Colloidal Injection Molding of Ceramics (CIMC) Based on Gelation 1 What is Colloidal Injection Molding? 3 Colloidal Injection Molding of Ceramics (CIMC) 3 The Flowchart of CIMC 4 The Machine of Colloidal Injection Molding of Ceramics 5 Pressure-Induced Forming 6 Effect of Hydrostatic Pressure on Solidi?cation 6 Homogeneity of the Green Bodies 7 Controlling the Inner Stress in the Green Body 7 Storage Stability of Ceramic Slurries 10 The Importance of Storage Stability of Slurry 10 Chemical Stability 10 Inhibitor for Slurry Storage 12 To Prepare High Reliability Ceramic Parts with Complex Shapes: Aqueous Colloidal Injection Molding 13 Summary 14 References 16 Gel Tape Casting of Ceramic Substrates 17 Fundamental Principle and Processing of Aqueous Gel Tape Casting 19 Tape Casting Types and the Raw Materials Used 19 Polymerization of the Monomer 23 In?uence Factors on Polymerization of the Monomer 31 Processing of the Gel Tape Casting 37 _x00C_x Contents Characteristics of Slurries Used for Aqueous Gel Tape Casting 40 Properties of the Aqueous Ceramic Slurries with Binder 40 In?uence of Dispersants on Stability and Rheology of Aqueous Ceramic Slurries with Organic Monomer 45 In?uence of Plasticizer on Properties of Aqueous Ceramic Slurry with Organic Monomer 49 In?uence of PH Value on Properties of Slurry with Organic Monomer 50 Effects of Surfactant on Wetting and Green Tape Releasing (Separating) 51 Foam and Pore Elimination 53 Sintering of Green Tape Prepared by Slurry 54 Aqueous Gel Tape Casting with Styrene-Acrylic Latex Binder 55 The Importance of Binders in Gel Tape Casting Process 55 The Forming Film Mechanism of Latex Binder 58 Rheological Properties of the Alumina Slurries with Binder 60 The Physical Properties and Microstructure of Green Tapes 61 A Gel Tape Casting Process Based on Gelation of Sodium Alginate 63 Why Study on Tape Casting of Sodium Alginate 63 The Preparation of Aqueous Alumina Suspensions with Sodium Alginate and Calcium Phosphere Tribasic . . . 65 Control of the Gelation of Sodium Alginate 66 Characterization of Green Tapes 68 Spray Trigger Fast-Curing for Gel Tape Casting Process 70 The Idea of Spray Trigger Fast-Curing 70 Outline of the New Process 70 Summary 71 References 75 Gelation Forming Process for Toxicity-Free or Low-Toxicity System 79 Gelation Forming of Ceramic Suspension with Agarose 80 Characteristics of Agarose 80 The Effect of Agarose Contents on the Rheology of Aqueous Ceramic Suspensions 82 The Forming Courses of the Aqueous Ceramic Suspensions with Agarose 84 _x00C_Contents xi Alumina Casting Based on Gelation of Gelatin 88 Characteristics of Gelatin 88 The Gelation Process of the Ceramic Slurry with Gelatin Solution 91 Preparation of Green Body Using Slurry with Gelatin Solution 93 A Casting Forming for Ceramics by Gelatin and Enzyme Catalysis 95 Research Background 95 Gelation Mechanism of Gelatin Solution with Urea Under Enzyme Catalysis 97 Rheology and Zeta Potential of Alumina Suspension Containing Gelatin and Urea 99 Coagulation Forming and Microstructure of Green Body 100 Alumina Forming Based on Gelation of Sodium Alginate 102 Research Background 102 Gelation Principle of Sodium Alginate 104 Preparation Process of Alumina Green Bodies and Samples by Sodium Alginate 107 Gelcasting of Silicon Carbide Based on Gelation of Sodium Alginate 110 Research Background 110 Effect of Dispersant on the Colloidal Behavior of the SiC Suspension 112 Rheological Property of SiC Suspension 113 Sedimentation Behavior of the SiC Suspension 115 Gelation Principle and Process of the Alginate Solution 116 Gelation of the SiC Suspension with Alginate 116 Alumina Gelcasting with a Low-Toxicity System of HEMA 119 Academic Idea and Research Program 119 Colloidal Chemistry and Rheological Property 120 Binder Burnout and Application of the New System 122 A Synergistic Low-Toxicity Gelcasting System by Using HEMA and PVP 124 Academic Idea and Research Program 124 f Potentials and Rheological Properties 125 Activation Energies and Solidi?cation 128 _x00C_xii Contents Green Strengths and Microstructures 129 Exfoliation Elimination Effect and Analysis of the Interaction Between PVP and HEMA Molecules 131 References 134 Generation, Development, Inheritance, and Control of the Defects in the Transformation from Suspension to Solid 139 Rheological Behaviors of Aqueous Ceramic Suspensions 141 Rheological Behaviors of Aqueous Alumina Suspensions 142 Effect of Rheological Properties of Suspension on Mechanical Strength of Ceramics 145 Effects of Solid Volume Fraction on Colloidal Forming 153 Generation and Development of Defects 158 Generation Mechanisms of Agglomerations in Ceramic Suspensions 158 In?uences of Idle Time on Microstructures and Mechanical Properties of Green Bodies by Direct Coagulation Casting 165 Effect of Ionic Conductance on Preparation of Highly Concentrated Suspension 174 Academic Idea and Research Program 174 The Relationship Between Ion Conductivity Constants and Solids Volume Loading 176 Control of Inner Stress in Green Body 181 Origin, Transformation and Control of Inner Stress in Green Body 181 Release and Control of Inner Stresses in Ceramic Green Body 187 Suppression of Surface Exfoliation with the Addition of Organic Agents 195 Suppression of Surface Exfoliation by Introducing Polyacrylamide (PAM) into a Monomer System in Suspension 195 Suppression of Surface Exfoliation by Introducing Polyethylene Glycol (PEG) into Monomer System in Suspension 203 References 221 _x00C_Contents xiii Gelcasting of Non-oxide Ceramics 225 Effects of Powder Surface Modi?cation on Concentrated Suspension Properties of Silicon Nitride 226 Contributing Factor and Elimination of Macropores in Silicon Nitride Green Bodies 226 Effect of Foreign Ions on Concentrated Suspension of Silicon Nitride 232 Effects of Acid Cleaning and Calcinations on the Suspension Properties of Silicon Nitride 238 Effects of Liquid Medium and Surface Group on Dispersibility of Silicon Nitride Powder 249 Gelcasting of Silicon Nitride Ceramics 255 Preparation of Silicon Nitride Ceramics with Surface-Coated Silicon Nitride Powder 255 Preparation of Silicon Nitride Ceramics with Surface-Oxidized Silicon Nitride Powder 267 Preparation of Silicon Nitride Ceramics Using Combination Processing 276 Gelcasting of Silicon Carbide Ceramic and Silicon Nitride-Bonded Silicon Carbide Ceramic 287 Gelcasting of Concentrated Aqueous Silicon Carbide Ceramic 287 Gelcasting of Aqueous Slurry with Silicon Nitride-Bonded Silicon Carbide 294 References 306 Applications of New Colloidal-Forming Processes 311 Ceramic Microbeads 311 The Forming Principle of Ceramic Microbeads Based on Gelcasting 311 The Process of Preparing Microbeads 314 The Properties of Ceramic Microbeads 314 Summary 328 Improving the Breakdown Strength of the Rutile Capacitor 329 The In?uence of Sintering Additives on the Flow Behavior 331 Calcining of the Rutile Mixture 333 The Rheological Behavior of the Calcined Rutile Mixture 334 Gelcasting of the Calcined Rutile Mixture 335 Summary 336 _x00C_xiv Contents Thin-Wall Rutile Tube for Ozone Generator with High Dielectric Constant 338 Results and Discussions 339 Summary 341 Refractory Nozzle of Zirconia 342 Rheological Behaviors of Zirconia Suspensions with Different Dispersants 343 Sediment Stability of Zirconia Suspension with Different Dispersants 345 Preparation of Zirconia Refractory Nozzles 346 Summary 346 Water-Based Gelcasting of Lead Zirconate Titanate 348 Colloidal Chemistry and Rheological Behavior 350 Microstructure and Properties 354 Summary 357 References 357 New Methods and Techniques Based on Gelation 359 Development Overview and Application of Solid Freeform Fabrication 361 Development Overview of Solid Freeform Fabrication 361 Application of Solid Freeform Fabrication 362 Development Overview and Application of Freeze-Gelcasting 371 The Combination of Gelcasting and Freeze-Casting Technique 371 Fabrication of Ceramics with Special Porous Structures 372 Microstructure and Properties of Porous Alumina Ceramics 378 Mechanical Properties and Applications of Alumina Ceramics with Ultra-Low Density 382 Solidi?cation of Concentrated Silicon Nitride Suspensions for Gelcasting by Ultrasonic Effects 387 The Forming Method of Gelcasting Using Ultrasonic Effects 387 Preparation of Concentrated Silicon Nitride Suspensions 388 Ultrasonic Accelerated Solidi?cation 389 Comparison of Thermal- and Ultrasonic-Activated Solidi?cations 392 _x00C_Contents xv Novel Laser Machining Technology for Alumina Green Ceramic 394 Laser Machining Technology 394 Practical Application of Laser Machining Technology 395 References 402 Novel In-situ Coagulation Casting of Ceramic Suspensions 405 Direct Coagulation Casting of Ceramic Suspension by High Valence Counter-Ions 407 Direct Coagulation Casting by Using Calcium Iodate as Coagulating Agent 407 Direct Coagulation Casting by Using Calcium Phosphate as Coagulating Agent 423 Direct Coagulation Casting by Using Thermo-Sensitive Liposomes as Coagulating Agent 432 Direct Coagulation Casting from Citrate Assisted by pH Shift 442 Direct Coagulation Casting via High Valence Counter-Ions from Chelation Reaction 474 Dispersion Removal Coagulation Casting 501 Dispersant Reaction Method 501 Dispersant Hydrolysis Method 521 Dispersant Separation Method 532 References 541 Appendix A: The Testing, Analyzing and Sintering Methods Used in Authors' Research 549 Appendix B: The Raw Materials Used in Authors' Research 551 Index of Scholars 553 Index of Terms 561 Postscript 567